x86: add debug warnings to early_ioremap()

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 13 insertions, 6 deletions

diff --git a/arch/x86/mm/ioremap_32.c b/arch/x86/mm/ioremap_32.c
index 63f76ecae44..4bcd5e065df 100644
--- a/arch/x86/mm/ioremap_32.c
+++ b/arch/x86/mm/ioremap_32.c
@@ -306,12 +306,15 @@ void __init *early_ioremap(unsigned long phys_addr, unsigned long size)
 
         /* Don't allow wraparound or zero size */
         last_addr = phys_addr + size - 1;
-        if (!size || last_addr < phys_addr)
+        if (!size || last_addr < phys_addr) {
+                WARN_ON(1);
                 return NULL;
+        }
 
-        if (nesting >= FIX_BTMAPS_NESTING)
+        if (nesting >= FIX_BTMAPS_NESTING) {
+                WARN_ON(1);
                 return NULL;
-
+        }
         early_ioremap_nested++;
         /*
          * Mappings have to be page-aligned
@@ -324,8 +327,10 @@ void __init *early_ioremap(unsigned long phys_addr, unsigned long size)
          * Mappings have to fit in the FIX_BTMAP area.
          */
         nrpages = size >> PAGE_SHIFT;
-        if (nrpages > NR_FIX_BTMAPS)
+        if (nrpages > NR_FIX_BTMAPS) {
+                WARN_ON(1);
                 return NULL;
+        }
 
         /*
          * Ok, go for it..
@@ -351,11 +356,13 @@ void __init early_iounmap(void *addr, unsigned long size)
         unsigned int nesting;
 
         nesting = --early_ioremap_nested;
+        WARN_ON(nesting < 0);
 
         virt_addr = (unsigned long)addr;
-        if (virt_addr < fix_to_virt(FIX_BTMAP_BEGIN))
+        if (virt_addr < fix_to_virt(FIX_BTMAP_BEGIN)) {
+                WARN_ON(1);
                 return;
-
+        }
         offset = virt_addr & ~PAGE_MASK;
         nrpages = PAGE_ALIGN(offset + size - 1) >> PAGE_SHIFT;